Music...why is it so, so, musical?

I know there are rules to making chords that sound nice, chords that sound sad, and combinations of notes that sound bad, bad, bad. My question is why? Why does our brain think these combinations of frequencies sound good, bad or sad together? Some preferences may be acquired but some of this must be hard-wired. Does anyone know how?

Because that’s just the way I write them.


I’ve been alive for ever, and I wrote the very first songs.

One aspect of the musicalness of music lies in what my Intro to Music Appreciation textbook calls “the miracle of the octave” which basically says that notes that are an octave apart have whole number ratios of their frequencies. In other words, if middle C is 220Hz, the next C higher is 440Hz, then 880Hz and so forth.

choosybeggar asked:

What a great question!

Preferences in music vary widely from culture and people within the same culture. You may prefer country, I may prefer death metal.

There are some sequences of tones that seem to have a near-global appeal. What the Western world commonly refers to as the Pentatonic Minor (a 5-note scale - In C: C Eb F G Bb) is also widely used in Asian and Indian music.

The tri-tone (also known as diminished 5th or augmented 4th - In C: C-F#/Gb) was known as diabolus in musica by the earlier Catholic Church and forbidden (as much as they were able) in popular music, due to the chaotic and evil sound. This interval is present in nearly every heavy metal song ever written for the same reason.

So, there is evidence that certain things are “hard-wired” in the brain. But some chords and melodic patterns are not so easily understood and appreciated immediately, as anyone who listens to free jazz will certainly attest (usually with much snobbery about being able to appreciate such music).

Intervals in music are generally characterized as consonant (pleasing) or dissonant (displeasing). The two main types of dissonance are harmonic (occuring at the same time) and melodic (occuring in sequence).

Perhaps the main consideration of what constitutes pleasing and displeasing from a mathematical standpoint is the ratio of each note’s frequency to the other.

For example, under Pythagorean Tuning fifths have a ratio of 3:2. This is a stable and pleasing consonance. Octaves are (as USCDiver pointed out) 2:1. These ratios as well as the reliance of fifths and octaves to very consonant is a common thread through nearly all music, regardless of cultural origion.

Of course, one purpose of just intonation is to provide a more “useable” ratios amongst all the intervals in that particular scale.

A great FAQ on the evolution of modern music is here. This touches on the OP in several different ways and much deeper than I am able.

Perhaps one way of thinking about what makes the right notes is to hear someone tuning a guitar by ear. As the string being tuned changes pitch in relation to a reference note, a wavering or cycling sound is heard. This is an unpleasant ratio that is resolved when the string is in tune.

As for why major is “happy” and minor is “sad”, etc. I really have no idea…except it sounds that way to me.